Automatic slack adjuster



June 5, 1934. ANDERSON 1,961,919

AUTOMATIC SLACK ADJUSTER Filed Sept. 12. 1932 2 Sheets-Sheet. l

Q/arle i. Qmderaarfl, Y

June 5, 1934. H. E. ANDERSON AUTOMATIC SLACK ADJUSTER Filed Sept. 12,1932 ZSheets-Sheet 2 amnion.

Patented June 5, 1934 p UNITED STATES PATENT OFFICE AUTOMATIC SLACKADJUSTER Harley E. Anderson, Chicago, 111., assignor to Grip NutCorporation, Chicago, 111., a corporation of Illinois ApplicationSeptember 12, 1932, Serial No. 632,787

18 Claims. (Cl. 188-202) The invention relates to improvements in air inthe specification, drawings and claims ap brake systems and hasreference! more particupended hereto.

larly to automatic slack adjusting means for reg- In the drawings whichillustrate an embodiulating the brake rigging to give constant brakement of the invention and wherein like reference shoe clearance andmaximum efficiency. characters are used to designate like parts- The A.R. A. regulations are that the piston Figure 1 is a plan view of. theunder-frame of travel of the brake cylinder must be maintained a railwaycar showing that portion of the founat not less than seven inches ormore than nine dation rigging associated with the air brake cylincheswith eight inches being the desired travel inder equipped with theautomatic slack adjuster 1 10 for the most efficient operation of theair brake of the present invention;

equipment. At present the adjustment is gener- Figure 2 is a sectionalview taken along line ally made by manually changing the fulcrum 2--2 ofFigure 1 showing parts of the device in point of the dead truck lever,the fulcrum strap elevation;

of which is provided with a number of pin open- Figure 3 is a detailsectional view longitudinally 1 5 ings so that the piston travel can belengthened of the turn-buckle taken on line 3-3 of Figure 1. orshortened, depending on the particular open- Figure 4 is a sectionalview takenon line 44 ing employed. Such manual adjustment is unof Figure3 showing the association of the ratchet desirable as it is almostimpossible to maintain wheel with its housing and pivoted gravity dog;the correct piston travel and often slack in the Figure 5 is a viewsimilar to Figure 4 showing 20 brake rigging is taken up by adjustingone lever additional structure for preventing unintentiononly of atruck, which throws all the brake levers al turning of the ratchetwheel; and

out of line, at times causing the foundation rig- Figure 6 is afragmentary elevational view of ging to foul. a passenger brake cylindershowing the method The present invention provides for automatiofoperatively connecting the slack adjuster with 25 cally controlling thepiston travel by the provithe solid piston rod of the same.

sion in the pull rod of the brake rigging of a The foundation riggingshown in Figure 1 is turn-buckle operatively connected for actuationassociated with a freight car consisting of spaced by the piston of thebrake cylinder. A desirable center sills l0 and 11, the lattersupporting by feature of the device is that while it acts automeans ofbrackets 12 an air reservoir 14 and 3o matically it is free fromsprings, depending on freight brake cylinder 15. The brake cylinder therelease spring within the air cylinder to cause is provided with theusual piston not shown and the adjuster to function as the pistonreturns to connected hollow piston sleeve 16 which proreleased positionin the cylinder. Also the presjects outwardly of the non-pressure head17, the ent installation saves the expense of the usual piston andhollow piston sleeve being maintained 3e fulcrum strap for the deadlevers as the same in retracted position by the release spring 18 conmaybe permanently fastened to the truck bolster. fined between the pistonand the non-pressure One of the objects of the present invention is head1'7. The piston of the air brake cylinder acto provide mechanism of theabove general chartuates the push rod 20 supported by the hollow acterof simple and practical construction and piston sleeve and pivotallyconnected at its outso which can be applied to the foundation rigging erend as at21 to a cylinder lever 22 supported without material alterationin the existing strucfor movement from the center sills by supportsture. 23. The cylinder lever connects at its other end A further objectis to provide a slack adjuster with means joining with the live leversof the for controlling the travel of the piston of the air brake riggingon the forward truck and interb-rake cylinder automatically within thelimits mediate 'its ends at 24 with a pull rod 25,100 required by the AR. A. as the brake shoes wear, Through suitable connections well knownto which will be substantially fool-proof, which will those skilled inthe art, and for that reason not be so constructed as to preventfouling, and disclosed, the pull rod connects with the live wherein easyand quick manual regulation is postruck levers on the rearward truck sothat actua- L'; sible for positioning the various parts for the tions ofthe piston of the air brake cylinder are insertion of new shoes.simultaneously imparted to both trucks for ap- With these and variousother objects in view, plying the brakes to the car wheels. Hand brakethe invention may consist of certain novel fea actuating means isindicated generally at 26, the tures of construction and operation aswill be chain having connection with the cylinder lever L; more fullydescribed and particularly pointed out 22 at 21 to cause a relativemovement of the push rod and connected end of the cylinder lever towardthe right in applying the brakes by hand without in any way disturbingthe position of the piston or hollow piston sleeve.

After a time successive application of the brakes of the car wheels sooncauses the brake shoes to wear with the result that the clearancebetween the brake shoe and the car wheels is increased, resulting in anincrease in piston travel to apply the brakes. To maintain the idealpiston travel requires frequent adjustment of the brakes and accordinglythe invention provides an automatic adjuster whereby the pull rodconnecting the cylinder and floating levers can be shortened to take upthe slack in the brake rigging on the trucks and when new shoes areinstalled to replace the old ones the pull rod can be manuallylengthened to provide the necessary slack for accommodating the newshoes.

Referring more particularly to Figures 1 and 2 the hollow piston sleeveis disclosed as having riveted to its projecting end a collar 2'7provided with upstanding pin 28 for pivotally securing to the collar andthe sleeve an arm 30. Pivotal- 1y connecting with the arm 30 at 31 is alever 32 supported for rotation in the hinge bracket 33 suitably securedby means of rivets to support 34, in turn riveted to the base of thecenter sill 11. The bifurcated arm 35 has non-rotative securement tolever 32 and at its outer end connects by means of pin 36 with atransverse member in the form of a strap 37 supported at its oppositeend from center sill 10 by the depending bracket 38.

Centrally of the strap 37 are provided side walls flanged outwardly at40 for receiving the shaped ends 41 of the cover or housing 42. Thecover encloses a ratchet wheel 43 mounted on a turnbuckle to bepresently described, and is provided with hubs 44 which contact withsemi-circular portions 45 on the cover, and since the cover is held tothe strap 3'7 it will be seen that the structure provides for rotationof the ratchet Wheel within the cover while maintaining the ratchetwheel and strap in desired spaced relation. Also formed centrally of thestrap are a pair of depending lugs 46 apertured for receiving the pivotpin 47 serving to pivotally secure to the strap the gravity dog 48having a latch 56 projecting through an opening provided in the strapand adapted to engage with the teeth on the ratchet wheel 43. The latchof the gravity dog is formed with a shoulder 51 which engages one end ofthe opening in the strap to position the latch upright.

The adjuster proper comprises a turn-buckle in the form of an elongatedtube 52 threaded internally as at 53, the threads being grooved at 54 sothat the same can be continuously supplied with oil admitted to theinterior of the turn-buckle through the opening normally closed by theplug 55. In applying the adjuster to the pull rod 25 the same has aportion removed and the ends are threaded so that they can be connectedto the adjuster by being threaded to the ends of the turn-buckle. Inthose cases where it is necessary to equip rigging already in operationon a railway car the turn-buckle is provided with extensions 56 and 57threaded at their inner ends for association with the turn-buckles andwhich are suitably welded or otherwise secured to the separated portionsof the pull rod. In either case the turn-buckle has threaded engagementwith the separated sections of the pull rod and it is to be noted thatthe threads of one end of the turn-buckle are right hand, while those onthe other end are left hand, so that rotation of the turn-buckle servesto shorten or lengthen the pull rod. A portion of the exterior surfaceof the tube 52 is formed of hexagonal shape for association with. theratchet wheel 43 which has limited longitudinal movement on the tube,while the remaining portion thereof is circular for engagement with thesupporting strap 58 depending from the center sill 11.

It will be understood that if for any reason the adjuster fouled itwould cause the piston of the air brake cylinder to fail to release,with he result that the brake shoes would drag or bear against thewheels causing brake burn on the tread of the wheels and fiat spots. Inorder that the adjuster may at all times be free to operate theinvention provides that the threaded ends of the pull rod becontinuously immersed in oil.

For this purpose the bore of the turn-buckle is grooved at 54 and endcaps 60 are provided for retain'mg a felt washer 61 which serves toclose the ends of the turn-bucl :le,.holding the oil within the same.The groove forms a by-pass for the oil, allowing passage of the samefrom the center of the turn-buckle to the ends as the threaded ends ofthe pull rod come together and to return to the center chamber as thethreaded ends are moved outwardly.

The device as above described is actuated by movement of the hollowpiston sleeve 16 toward the right, Figure 1, upon the application of thebrakes to the car wheels. As the collar 27 is fixediy secured to thesleeve the same is carried outwardly rotating lever 32 and impartingmovement to the strap 37 in a direction toward the left. As the gravitydog 48 is carried by the strap the latch 50 will be located some irhereunder the ratchet wheel 43, the particular location depending on theextent of travel of the piston sleeve. The present inventioncontemplates the proper proportioning of the parts so that the latch 50will be located under the ratchet wheel and within the toothed spaceformed by the two lower-most teeth of the ratchet when the piston travelis t inches. When this condition occurs and the brakes are released itwill be seen that the piston immediately returned to initial position bythe release springs 18 thus causing actuation of the strap 37 in adirection toward the right, Figure 2, and as the strap carries dog 18the latch 50 will contact with a tooth on the ratchet wheel 43 to causerotation of the wheel. As the extent of movement of the latch 50 is verysmall the rotation imparted to the ratchet wheel is sufficient to rotatethe same only one tooth, which rotation l'kewise takes place withrespect to the turnbuckle to cause shortening of the pull rod 25,thereby taking up the slack in the brake rigging.

With the piston travel greater than eight inches a greater degree ofrotation will be imparted to lever 32 to cause further movement of thestrap 37 toward the left, whi h movement may be sufficient to locate thelatch 50 to the left of the ratchet wheel whereupon rotation will beimparted to the ratchet wheel upon release of the brakes to the extentof two teeth which will result in a more pronounced shortening of thepull rod 25. On the other hand, should the piston travel approximateseven inches it will be seen that the latch 50 will not be movedsufficiently to engage with a tooth on the ratchet wheel and accordinglyno rotation of the ratchet wheel nor actuation of the turn-buckle toshorten the pull rod will take place. The present device thus respondsto the extent of piston travel and when the same is beyond the ideal theturnbuckle is actuated to cause shortening of the pull rod and thetaking upof slack in the brake system. When the brake shoe clearance andpiston travel are such that no excess slack exists the turn-buckle isnot actuated and adjustment of the brake rigging is not effected untilconsiderable brake shoe wear occurs.

After a set of brake shoes have worn and a new set are to be applied theoperator in order to make available sufiicient slack in the systemsimply rotates the turn-buckle by hand, lengthening the middleconnecting rod to its original length. The turn-buckle is much easier toreach and safer than bending over the axle at each truck to get at thedead levers and also there are no cotter pins or brake lever pins toremove. As the turn-buckle is part of the pull rod the same has freelongitudinal movement with respect to the ratchet wheel to permit thebrake rigging to adjust itself as the trucks round a curve or pass overa switch. It is also to be noted that the pawl and ratchet which operateupon reciprocation of the strap member to rotate the turnbuckle toshorten the pull rod are normally disconnected. That is, the parts arelocated in spaced relation when the brakes are in released position.This normal disconnection of the parts is desirable as it permits manualadjustment of the rigging to lengthen the pull rod without re quiringthe disconnection or release of any part. The additional structure shownin Figure 5 is added in order to prevent unintent onal rotation of theratchet wheel due to vibration of the foundation rigging, and consistsin the provision of a latch 65 pivoted at 66 to members projecting fromthe strap 37 and resiliently urged by coil spring 67 in a clockwisedirection against a stop provided so as to maintain the latchsubstantially horizontal. As the latch is carried by the strap movementof the latter serves to remove the latch from association with theratchet wheel so that the same does not interfere with the rotation ofthe wheel by latch 50. When, however, it is desired to manually rotatethe wheel the latch 65 may be removed by graspng the finger piece 68 androtating the latch against the coil spring 67.

In the application of the present invention to a freight brake cylinderit will be noted that the hollow piston sleeve has fixedly secured toits outer end a collar 27. This collar functions as asafety featuresince the same is located on the sleeve to the outside of thenon-pressure head and retains the release spring within the head whenthe same is removed for cleaning the brake cylinder. The practiceheretofore required the operator to insert a pin in holes provided inthe end of the hollow piston sleeve before attempting removal of thenon-pressure head. This pin or other means used would often fail, releasng the non-pressure head and release spring and causing injury to theoperator. As the collar 27 is securely riveted to the hollow pistonsleeve such dangers are eliminated by the installation of the presentdevice. I

In passenger cars a structural difference exists between the brakecylinder equipment on the same and that employed on freight cars in thatthe hollow piston sleeve is omitted and the piston rod connects thecylinder lever directly with the piston. In Figure 6 the passenger brakecylinder 115 having the non-pressure head 117 is shown with a solidpiston rod 120 extending from the piston connected thereto through thehead and beyond for securement to the jaw 170 by-the bolt 1'71. By meansof the brake pin 172 the cylinder lever 22 can be pivotally connected tothe jaw and thus the piston rod, and accord'ngly any movement of thepiston is transmitted to the cylinder lever which is returned after abrake application by the release spring 118. For at taching the arm 30to the jaw the brake pin 1'72 has an extension 173 and the constructionop-- crates in the same manner as that of the freight cylinder since arm30 is caused to rotate lever 32 upon each appl cation of the brakes withthe parts being returned by the release spring as described. Since thepiston rod 120 and hollow piston sleeve 16 both have varying extent ofmovement, depending on the piston travel, the adjuster functions in likemanner'whether associated with freight or passenger brake equipment.

It is to be understood that I do not wish to be limted by the exactembodiment of the device shown, which is merely by way of illustrationand not limitation, as various and other forms of the device will ofcourse be apparent to those skilled in the art without departing fromthe spirit of the invention or the scope of the claims.

I claim:

1. In a regulator for foundation brake rigging, a pull rod, an air brakecylinder for actuating said rod, an adjuster including a turn-bucklepositioned intermediate the ends of said rod. a ratchet wheelnon-rotatably but slidably mounted on said turn-buckle, reciprocatingmeans actuated by said brake cylinder, a latch carried by said means andadapted to engage the wheel to cause rotation thereof, said latch andwheel being positioned in spaced relation when the brakes are releasedso that rotation of the wheel occurs only upon a predetermined extent ofpiston travel upon brake application.

2. In a regulator for foundation brake rigging, a pull rod, an air brakecylinder for actuating said rod, said cylinder including a piston sleeveand release spring, an adjuster in the form of a turn-buckle positionedintermediate the ends of said rod, and reciprocating means actuated inone direction by the brake cylinder upon a brake application and in theother direction by the release spring for rotating said turn-buckle.

3. In a regulator for foundation brake rigging, a pull rod, an air brakecylinder for actuating said rod, said cylinder including a piston sleeveand release spring, an adjuster in the form of a turn-buckle poistionedintermediate the ends of said rod, and reciprocating means disposednormally to the turn-buckle and operatively connecting with the piston(sleeve, said means being actuated in one direction by the brakecylinder upon a brake application and in the other direction by therelease spring for rotating said turn-buckle.

4. In a regulator for foundation brake rigging, a pull rod, an air brakecylinder for actuating said rod, said cylinder including a piston sleeveand release spring, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, a reciprocating member disposednormally to the turn-buckle and operatively connecting with the pistonsleeve, said member being actuated in one direction by the brakecylinder upon a brake application and in the other direction'by therelease spring, and means between the member and turn-buckle operatingto rotate the latter when the extent of reciprocation exceeds apredetermined amount. 7

5. In a regulator for foundation brake rigging, a pull rod, an air brakecylinder for actuating said rod, said cylinder including a piston sleeveand release spring, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, a reciprocating member disposednormally to the turn-buckle and connecting with the piston sleeve, saidmember being actuated in one direction by the brake cylinder upon abrake application and in the other direction by the release spring, aratchet wheel non-rotatably mounted on the turn-buclde, and a latchcarried by the member, said latch operating to rotate the wheel when theextent of reciprocation exceeds a predetermined amount.

6. Automatic slack adjusting means for foundation brake rigging having apull rod including a turn-buckle forming part of said rod, a ratchetwheel on said turn-buckle, and reciprocating means actuated by the brakecylinder upon an application of the brakes for engaging and rotatingsaid wheel, and other means carried by the reciprocating means forpreventing inadvertent rotation of the wheel.

'7. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cyl inder for actuating said rod, said cylinderhaving a piston sleeve, an adjuster including a turnbuckle positionedintermediate the ends of said pull rod, a ratchet wheel non-rotatablybut slidably mounted on said turn-buckle, a recipro eating strap membersupported for movement from the underframe of the car and carrying alatch member for engaging with the ratchet wheel, and connections havingpivotal association with the car underframe for operatively connectingthe strap member and piston sleeve of the cylinder.

3. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve and a release spring, an adjuster including a turn-bucklepositioned intermediate the ends of said rod, a ratchet wheelnon-rotatably but slidably mounted on said turn-buckle, a reciprocatingstrap member supported for movement from the underframe of the car andcarrying a latch member for engaging with the ratchet wheel, and meansincluding a bell crank having pivotal. association with the carunderframe for operatively connecting the strap memher and pistonsleeve, whereby said strap member is reciprccated in one direction by abrake application and in the reverse direction by the release spring,said bell crank being constructed and arranged to materially decreasethe distance the strap moves relative to that or" the piston sleeve andto increase the force exerted by the strap in like proportion.

9. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, means supporting said turnbuckle fromthe car frame permitting longitudinal movement thereof but preventinglateral movement of the turnbuckle, a ratchet wheel nonrotatably butslidably mounted on said turnbuckle, a strap mem ber supported forreciprocating movement from the car underframe and having a latch memberfor engaging with the ratchet wheel, and actuated by the piston sleeveof said brake cylin der for imparting reciprocating movements to saidstrap member.

10. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, means supporting said turnbuckle fromthe car frame permitting longitudinal movement thereof but preventinglateral movement of the turnbuckle, a ratchet wheel nonrotatably butslidably mounted on said turnbuckle, a strap member supported forreciprocating movement from the car underframe and having a latch memberfor engaging with the ratchet wheel, and means actuated by the pistonsleeve of said brake cylinder for imparting reciprocating movements tosaid strap member, said latch member being spaced from the ratchet wheelwhen the brakes are released but engaging the wheel to cause rotationthereof upon a predetermined extent of movement of the sleeve duringbrake application.

11. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, means supporting said turnbuckle fromthe car frame permitting longitudinal movement thereof but preventinglateral movement of the turnbuckle, a ratchet wheel nonrotatably butslidably mounted on said turnbuckle, a strap member supported forreciprocating movement in the car underframe and having latch means foren aging the ratchet wheel upon reciprocating movement thereof, andmeans actuated by the piston sleeve of said brake cylinder for impartingreciprocating movements to said strap member, said means including abell crank mounted for pivotal movement on the car underframe.

12. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve, an adjuster in the form of a turn buckl positionedintermediate the ends of said rod, a ratchet wheel nonrotatably butslidably mounted on said turnbuckle, a housing for said ratchet wheel, areciprocating strap member supported for movement from t, e carunderframe and having a latch member for engaging with the ratchet wheelduring said reciprocating movement, means forming part of said housingfor maintaining the strap member and ratchet Wheel in proper relation,and connections operatively connecting the strap member and pistonsleeve of the brake cylinder, whereby reciprocating movements areimparted to the strap member upon movement of the piston sleeve duringapplication of the brakes.

13. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston sleeve, an adjuster in the form of a turnbuckle positionedintermediate the ends of said rod, a ratchet Wheel nonrotatably butslidably mounted on said turnbuckle, a reciprocating strap membersupported for movement from the car underframe, connections operativelyconnecting the strap member and the piston sleeve of the cylinder, alatch pivotally carried by the strap member to one side of the ratchetwheel for engaging the ratchet wheel to rotate the same upon apredetermined extent of movement of the strap member in a certaindirection, and locking means carried by the strap member and located tothe other side of the ratchet wheel, said locking means normallyengaging the ratchet wheel but being withdrawn therefrom by movement ofthe strap member in said certain direction.

14. In a regulator for foundation brake rigging, an air brake cylinderfor actuating said rod, an adjuster in the form of a turnbucklepositioned intermediate the ends of said rod, said turnbuckle comprisingan elongated tube threaded internally for receiving the threaded ends ofsaid pull rod, a ratchet wheel mounted on said turnbuckle, a housing forthe ratchet wheel, reciprocating means actuated by the brake cylinderfor rotating said wheel causing rotation of the turnbuckle to take upslack in the rigging, said reciprocating means being engaged by thehousing and having movement substantially at right angles to theturnbuckle, and means supporting the turnbuckle from the car underframepermitting longitudinal movement thereof but preventing lateralmovement.

15. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder having piston actuated means foractuating said rod to apply the brakes, an adjuster in the form of aturnbuckle positioned intermediate the ends of said rod, a ratchet Wheelnonrotatably but slidably mounted on said turnbuckle, a reciprocatingstrap member supported for movement from the car underframe, connectionsoperatively connecting the strap member and the piston actuated means ofsaid cylinder, said strap member being located under the ratchet wheeland carrying a pivotally mounted latch, and counter-balancing means formaintaining the latch in vertical position, whereby predetermined extentof movement of the strap member in a certain direction will result inthe latch operatively engaging with the ratchet Wheel to cause rotationthereof whenthe strap has movement in the opposite direction.

16. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod, said cylinderhaving a piston rod, an adjuster including a turnbuckle positionedintermediate the ends of said pull rod, a ratchet wheel nonrotatably butslidably mounted on said turnbuckle, a reciprocating strap membersupported for movement from the underframe of the car and carrying alatch member for engaging with the ratchet Wheel, and connections havingpivotal association with the car underframe for operatively connectingthe strap member and piston rod of the cylinder.

17. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston rod and a release spring, an adjuster including a turnbucklepositioned intermediate the ends of said pull rod, a ratchet wheelnonrotatably but slidably mounted on said turnbuckle, a reciprocatingstrap member supported for movement from the underframe of the car andcarrying a latch member for engaging with the ratchet wheel, and meansincluding a bell crank having a pivotal association with the carunderframe for operatively connecting the strap member and piston rod,whereby said strap member is reciprocated in one direction by a brakeapplication and in the reverse direction by the release spring, saidbell crank being constructed and arranged to materially decrease thedistance the strap moves relative to that of the piston rod and toincrease the force exerted by the strap in like proportion.

18. In a railway car, in combination with foundation brake rigging, apull rod, an air brake cylinder for actuating said rod and having apiston rod, and adjuster in'the form of a turnbuckle positionedintermediate the ends of said pull rod, meanssupporting said turnbucklefrom the car frame permitting longitudinal movement thereof butpreventing lateral movement of the turnbuckle, a ratchet wheelnonrotatably but slidably mounted on said turnbuckle, a strap membersupported for reciprocating movement in the car underframe and havinglatch means for engaging the ratchet wheel upon reciprocating movementthereof, and means actuated by the piston rod of said brake cylinder forimparting reciprocating movements to said strap member, said meansincluding a bell crank mounted for pivotal movement on the carunderframe.

HARLEY E. ANDERSON.

